David Norris (Independent) | Oireachtas source

This is the crux of the matter. It is absurd for a Minister for Arts, Heritage, Regional, Rural and Gaeltacht Affairs to come in here and blather on about hedges. What have hedges got to do with heritage? It is a complete and absolute nonsense. The absence of scientific evidence on the part of the Minister has been underlined throughout the debate. No survey has been done and this is disastrous. It is appalling that the Government would introduce policy based on no scientific research whatsoever.

The Heritage Bill proposal to allow burning in March would have a very serious impact on upland breeding birds. Birdwatch Ireland, a professional body engaged in this area, presented the best available data to the Minister but the science is being totally ignored. It might as well not have been done. We need Irish data so we need a proper pilot study, not a mass implementation of a policy which is unsupported by science. The necessary research must take place before this is implemented.

What science underpins the proposed changes to ensure birds are not impacted? What evidence has the Minister got for this? She has presented none to this House. If a pilot study shows that nesting birds have been impacted what will the Government's policy objectives be? Will this alter the situation? Can we have the details of what secondary legislation is envisaged by the Government?

According to Derek Mooney, a well-known populariser of natural history, modern farming practice has taken its toll on wildlife and the destruction of hedgerows has greatly reduced the cover of mammals and birds. He said seed-eating birds will decline drastically in numbers and the shortage of insect larvae will make it difficult for birds to raise their young. Three quarters of an hour ago in this House I adverted to the impact on the moth and butterfly population so I will not regurgitate it.

We do not have much scientific evidence in Ireland as it simply has not been done. I would, however, like to put on the record the results of a survey conducted by the University of Leeds on the impact of peat burning on the chemical composition of the landscape. It states that prescribed burning on peatlands was shown to have clear effects on peat hydrology, peat chemistry and physical properties, river water chemistry and river ecology. It is a substantial impact. It also states:

Burning reduces the organic matter content of the upper peat layers. The net result is that the peat is less able to retain important particles known as exchangeable cations. In other words, the peat in burned sites is deprived of chemicals which are important for plant growth and for buffering acidic rainfall. [By burning peat we are creating conditions that are adverse to important plant growth.] Lower concentrations of nutrient elements found in peat soils in burned river basins do not support the idea that burning enriches the peat with nutrients from ash. [We are often told that by burning on grassland, gorse and scrub areas one gets a fresh growth of grass but this does not appear to be the case with regard to peatlands.] Rivers draining burned catchments were characterised by lower calcium concentrations and lower pH relative to rivers draining unburned catchments. Rivers draining burned sites had higher concentrations of silica, manganese, iron and aluminium compared to unburned catchments. There was no difference between burned and unburned catchments in peat nitrogen concentrations or in carbon to nitrogen ratios (high C/N is considered unfavourable to microbial decomposition of peat) ... Water-table depth is very important in peatlands for maintaining their stability and function as a carbon store. Water tables were found to be significantly deeper for burned catchments than for unburned ones. Deeper water tables would suggest a greater scope for degradation of the peat and loss of carbon to the atmosphere.

In other words it is carbon negative. The report further states that sphagnum is an important peat-forming species. Sphagnum grows on the bogs and in historical times it was used as a dressing for wounds as it has powerful medicinal properties. The report goes on:

Changes in the hydrological properties of the peat after fire make the peat less conducive to Sphagnum moss growth. River flow in catchments where burning has taken place appears to be slightly more prone to higher flow peaks during heavy rain. However, this was not a conclusive finding. Burning vegetation alters the natural peat hydrology in the upper layers of the peat affecting the balance of where water flow occurs. Recovery of many hydrological properties appears to be possible if a site is left unburned over many years. [This means the site shows a capacity to recover.] Thermal regimes appear to recover as vegetation regrows. This recovery was also seen in soil hydrology data from burned plots of different ages. Macroinvertebrates play a vital role in aquatic food webs by feeding on algae, microbes and detritus at the base of food chains before they themselves are consumed by birds, fish and amphibians. The research found that river macroinvertebrate diversity was reduced in burned sites. [This means there is a reduction in the small fauna in burnt areas.] In burned sites, river macroinvertebrate populations were dominated by groups that are commonly found in higher abundance in disturbed river systems, such as non-biting midge larvae (Chironomidae) and burrowing stonefly larvae (Nemouridae). Increases in the abundance of disturbance-tolerant taxa counteract declines and/or losses amongst some groups (e.g. mayflies) which are typically sensitive to reduced pH, increased aluminium and deposition of fine sediments. These changes show that burning increases the effect of biological stressors compared to unburned rivers.

All these things suggest a dramatic impact on the chemistry and ecology of peatlands. In addition, section 8 extends the burning period which would affect a significant proportion of our most threatened species. Upland burning has been shown to have some positive aspects but it is essential that threatened species are not wiped out. Among those species are curlew, which used to be a very common feature of the Irish landscape. Now one hardly ever hears the curlew's call, or the golden plover. This section needs to vigorously opposed and then rethought. I ask the Minister to do so.